In an interesting development, the Obama administration asked the Supreme Court of the United States to hear a case regarding GPS tracking devices and privacy. The case started when the police secretly placed a GPS tracking device on Atoine Jonas’s car, and used the information to help prove that he was dealing cocaine. An intermediate court threw the conviction out, but the Obama administration would like the Supreme Court to reinstate it.

There are very interesting Fourth Amendment issues in this case. But to me, the wider implications are far more important than just the police hiding tracking devices on cars.

GPS data is becoming very common for everyday people. Most “smart” phones (like the Android, iPhone and BlackBerry series) contain GPS systems. And lots of applications use this data in interesting ways: Yelp’s mobile application can show you nearby restaurants based on your GPS coordinates. But some applications (like games) also use your GPS data to target advertising. And some applications (like FourSquare) use it to broadcast your location to the world. The result is that there is a huge amount of movement tracking data being assembled about everyday people. If there is another Epsilon data breach, it could result in your movements being displayed to the world. If you’ve ever been anywhere private (a doctor’s office, a Planned Parenthood office, a bar, a job interview when you’re already employed, etc) it could be used against you. The same if burglars know you aren’t home at certain hours of the day (or that you are alone in a dark parking lot every night). We need to think carefully about what kind of protection is given to these GPS databases—not just against mis-use by law enforcement, but also how they are protected against hackers and others.

My takeaway: I don’t think I have anything to hide. But I still don’t want the world to be able to know where I am every moment. It’s a security and privacy threat, and one that not enough people are thinking about in the era of smart phones and data breaches. Maybe we need to consider GPS privacy before it’s too late?